Open Middle®
Directions: For each problem below, use the digits 1 to 9 at most one time each, to fill in the boxes to find the the greatest value for x that you can.
Hint
Where should the 9 go or not go? Where should the 1 go or not go?
Answer
(1/8)x + 2 = 9 yields a solution of 56.
(1/9)x – 8 = 7 and (1/9)x – 7 = 8 both have a solution of 135.
Source: Chase Orton and Mark Goldstein
A student asked me about the value of x and since it’s on the page twice it implies they are the same value. Great activity!!
NO PREP! INTERACTIVE GOOGLE SLIDES that go with this problem. Link Here:
shorturl.at/ivAQW
– You can assign this to student through google classroom.
– You can use it on an interactive board/tv
Amber, How did you create those slides? Thanks so much for sharing!
Thanks for sharing! This is awesome!
Thank you for sharing this!!
Is there an answer key?
Hi there. I have a question for this activity. You said that we could not repeat the same digits, but you repeated the 1 in your answer key. Is that a mistake or can we make our answers like that?
Think of it as two separate problems.